Since the electric industry in Pennsylvania was deregulated at the beginning of 2010, almost 40 percent of PPL Electric Utilities’ residential customers have switched to an alternative retail electric supplier, according to data recently released by the state Public Utility Commission.

Before deregulation, PPL was a monopoly. Customers in PPL’s service territory, which stretches across six regions in the western half of Pennsylvania, were forced to buy electricity from the utility at regulated prices and the utility, in turn, was responsible for distributing electricity to customers’ homes.

After deregulation, other electric companies were allowed to compete with PPL and each other to sell electricity. Customers could choose to buy their electricity from PPL at regulated prices or switch to a retail electric supplier. Meanwhile, PPL was tasked with continuing to distribute electricity to residents in its territory, no matter where customers chose to buy it.

Today, customers in PPL’s service territory have the power to choose which company they buy electricity from, but not which company distributes the electricity to their homes.

Public Utility Commission spokeswoman Denise McCracken said that while the savings customers get by switching from PPL to retail electric suppliers may not look like much at first, the 500,000 customers who switched saved an average of $100 a year.